People may feign physical or psychological illness for any number of reasons. Faked illness can get them out of work, military duty, or criminal prosecution. It can also help them obtain financial compensation through insurance claims, lawsuits, or workers' compensation. Feigned symptoms may also be a way of getting the doctor to prescribe certain drugs.

According to the American Psychiatric Association, patients who malinger are different from people who invent symptoms for sympathy (factitious diseases). Patients who malinger clearly have something tangible to gain. People with factitious diseases appear to have a need to play the "sick" role. They may feign illness for attention or sympathy.

Malingering may take the form of complaints of chronic whiplash pain from automobile accidents. Whiplash claims are controversial. Although some people clearly do suffer from whiplash injury, others may be exaggerating the pain for insurance claims or lawsuits. Some intriguing scientific studies have shown that chronic whiplash pain after automobile accidents is almost nonexistent in Lithuania and Greece. In these countries, the legal systems do not encourage personal injury lawsuits or financial settlements. The psychological symptoms experienced by survivors of disaster (post-traumatic stress disorder) are also faked by malingerers.

People malinger for personal gain. The symptoms may vary. Generally malingerers complain of psychological disorders such as anxiety. They may also complain of chronic pain for which objective tests such as x rays can find no physical cause. Because it is often impossible to determine who is malingering and who is not, it is impossible to know how frequently malingering occurs.

Malingering may be suspected:

• When a patient is referred for examination by an attorney
• When the onset of illness coincides with a large financial incentive, such as a new disability policy
• When objective medical tests do not confirm the patient's complaints
• When the patient does not cooperate with the diagnostic work-up or prescribed treatment
• When the patient has antisocial attitudes and behaviors (antisocial personality).

The diagnosis of malingering is a challenge for doctors. On the one hand, the doctor does not want to overlook a treatable disease. On the other hand, he or she does not want to continue ordering tests and treatments if the symptoms are faked. Malingering is difficult to distinguish from certain legitimate personality disorders, such as factitious diseases or post-traumatic distress syndrome. In legal cases, malingering patients may be referred to a psychiatrist. Psychiatrists use certain written tests to try to determine whether the patient is faking the symptoms.

In a sense, malingering cannot be treated because the American Psychiatric Association does not recognize it as a personality disorder. Patients who are purposefully faking symptoms for gain do not want to be cured. Often, the malingering patient fails to report any improvement with treatment, and the doctor may try many treatments without success.